Howdy hey everyone, I'm really new to modding in general and more specifically modding Binding of Isaac, and while I have been reading, learning, I have come to know a lot of the limitations at the moment (such as not being able to add new characters).

I was wondering how / if it is possible to add...
A) new or alt stages (or floors or chapters whatever you call them), that do not replace current content, but adds to it.
B) more loading images that will actually load
C) New Room types that don't replace curse rooms or libraries
D) Alt bosses that don't fully replace Mega Satan, or the Lamb, or Mom but can appear on the occasional play through

Also hope you guys are having a good day!

PS: Already have Basement Renovator